1. Field of the Invention
The present invention relates to a apparatus for ligating living tissues for inserting a living body cavity in a transendoscopic manner, thereby clipping a living tissue by a clip.
2. Description of the Related Art
Conventionally, it has been well known that a apparatus for ligating living tissues is disclosed in Jpn. UM. Appln. KOKAI Publication No. 2-6011 or Jpn. Pat. Appln. KOKAI Publication No. 63-267345, for example. In Jpn. UM. Appln. KOKAI Publication No. 2-6011, a clip and a manipulating wire are engaged with each other via a hook provided at a distal end portion of the manipulating wire and a connecting member provided at a tip end of the hook, the connecting member having a hook.
In addition, Jpn. Pat. Appln. KOKAI Publication No. 63-267345 discloses that a plurality of clips are incorporated in an introducing tube, these clips and a manipulating member are connected with each other with an aid of a substance with its low melting point, and the substance with its low melting point is fused while these clips and operating member are inserted into a body cavity so as to carry out clip ligation work continuously.
However, in the invention disclosed in Jpn. UM. Appln. KOKAI Publication No. 2-6011, only one clip can be mounted on a distal end of an introducing tube. Thus, only one clip can be used for each insertion into the body cavity through a forceps channel of an endoscope. Thus, in clipping a plurality of living tissues in a living body internal cavity, there has been a need to remove a clipping apparatus from the forceps channel of the endoscope every time, mount clips, and insert the mounted clips into the forceps channel again. Therefore, there has been a disadvantage that a complicated work is required, and too much time is required.
In addition, many cases of diseases such that a clip is applied to a bleeding site require very high emergency. Thus, in such cases of diseases, there has been a very serious problem that such a complicated, time consuming work is required.
In order to solve these problems, in Jpn. Pat. Appln. KOKAI Publication No. 63-267345, there is disclosed a clipping apparatus capable of carrying out ligation continuously by being inserted into a forceps channel only one time. In the thus-disclosed clipping apparatus, a plurality of clips are connected with each other by means of a substance with its low melting point. In addition, a temperature is controlled by a heating element provided at a tip end, thereby carrying out ligation continuously. That is, this structure is such that the heating element is heated up to a temperature at which the substance with its low melting point is fused, whereby these clips are disconnected from each other.
However, there has been a problem that providing a heating element at a distal end of a sheath complicates an apparatus structure, and requires another heat generating source. In addition, in order to open a clip made of a shape memory material, it is required to heat a clip up to a predetermined transform temperature T1. That is, after opening the clip, in order to fuse a substance with its melting point, and then, reliably ligate a living tissue, it is required to reliably control a relationship between a temperature T1 for opening a clip and a temperature T2 for fusing a substance with its low melting point. However, this temperature control has been very difficult. A clipping apparatus disclosed in Jpn. Pat. Appln. KOKAI Publication No. 63-267345 requires heating means for generating a heat during clip opening and during clip ligation. Thus, there has been a problem that clip ligation requires complicated work and much time.